Cardiovascular period 2

Coronary Artery Disease(CAD)

CAD is the most common type of heart disease. This illness occurs when the arteries that supply blood to heart, harden and narrow. Cholesterol and plague build up on the walls of the arteries, which decreases the blood flow. Since the blood can't get to the heart, the muscles cannot get the oxygen it needs. Therefore leading to chest pains, or angina. This condition may cause a heart attack.

Myocardial Infarction(MI)

This is just a long name for a heart attack. This occurs when the blood vessels that supply the blood to the heart are almost completely blocked. Therefore, not enough oxygen can get there. The plague that may build up in the vessels causes cracks or tears in the walls. The blood platelets stick to the tears and cause blood clots. This is what causes the blockage. The muscles then lack oxygen, and can't perform the necessary tasks.

Risk Factors:

• Increasing age increases vulnerability to the disease. This is because they may have more build-up in their blood vessels
• Children can inherit this problem from their parents
• People who smoke can develop it 2-4 times more often than a non-smoker
• High Blood Pressure increases the workload of the heart. Causing it to get stiffer, and thicken
• Obesity may cause CAD because the heart has to work harder, and it also worsens high blood pressure

Interesting Facts about the heart

1. The heart pumps about 2,000 gallons of blood everyday.
2. It beats about 70 times a minute, making it beat about 100,000 times a day.
3. The aorta(largest artery in the body) is the diameter of a garden hose. The capillaries are so small it takes about 10 of them to equal a human hair.
4. People think the heart is located on the left of the chest. When it is actually close to the center. It is tipped slightly to the left so it feels like it's there.

Name the main types of cells in your body

red blood cells- they transport carbon dioxide and oxygen throughout the body
white blood cells- fight infection
platelets- helps to clot blood

Describe the path blood travels through your body: include both pulmonary and systemic circulation.

pulmonary circulation- blood from right ventricle is pumped into the right or left pulmonary arteies goes to the lungs to get oxygen
systemic circulation- blood from left ventricle goes to the tissues of the body and the back of the right atrium
- oxygenated blood from the pulmonary veins passes from left atrium into left ventricle and then into the aorta where blood is distributed throughout the body





Major Functions of the Circulatory System
The circulatory has many vital responsibilites in our bodies. It delivers oxygen and digested food substances to all of your cells while removing carbon dioxide from them as well. Also, the circulatory system diposes harmful waste and toxins that would put your body in danger if accumulated. These harmful substances are mostly carbon dioxide, salts, and ammonia. The cirulatory system helps protect the body from disease with white blood cells, which destroy viruses and baceria present in the body. It can also help maintain a steady body temperature by absorbing heat from the cells that was created in the cell's energy production.

The Structure of a Cardiac Muscle Cell helps its function
The shape of heart muscle cells are a cylinder-like shape, but shorter than normal skeletal muscle cells. The cells are striated, or banded and have one nucleus per cell. Also, the muscle cells are all joined together by intercalated disks, which contain gaps and help maintain steady contractions in the heart's muscle cells.

Four Chambers

Right and Left Atria

• The contractions force bloo into the ventricles
• They receive blood from the veins
• The Atria are also known as reservoirs, which means blood returning from the veins collects in these places before entering the ventricles
• There are three major openings within the heart: Superior Vena Cava, Inferior Vena Cava, and the Coronary Sinus.
  • The superior and inferior Vena Cava carry lood from the body to the right atrium and four pulmonary veins
  • The Coronary Sinus drains blood from the heart

Right and Left Ventricles

• These are the parts of the heart which are the main pumoing chambers
• They release blood into arteries and force it to flow through the Circulatory System

Right: Pumps blood into the Aorta, which is two ventricles seperated from eachother by the muscular interventricular Septum

• Contractions increase pressure t 1/5 the pressure of the left ventricle; th pressure moves the blood trough Pulmonay Circulation

Left: The wall is thicker than the wall of the right ventricle

• the wall contracts with more force an generates a greater blood pressure; the higher blood pressure moves the blood through systematic circulation
• Both Ventricles pump the same amount of blood

Major Arteries/Veins/Valves

Pulmonary Trunk: Splits into the right and left pulmonary artieries; which carry blood to the lungs
Aorta: (arises from left ventricle) carries blood to the rest of our body
Coronary: on left side of the aorta
Circumflex: extends around the coronary sulcus on the left
Left Marginal Artery: this is located along the lateral wall of the left atrium
Right Coronary: this is located on the right side of the aorta and supplies blood to the heart and
sinoatrial node (groupof cells in the right atrial wall that keeps the heart's rhythmic rate balanced)
Left Coronary: located on the left side of the aorta; supplies blood o the heart ventricle and left atrium
Right Marginal: this artery extends along the wall of the right ventricle, which supplie the lateral of the right ventricle
Veins
Pulmonary Veins: carry blood from the lungs into the left Atrium
Cardiac Veins: drain blood fromt he Cardiac muscle and their pathways are parallel to the coronary arteries
Coronary Sinus: a large vein located within the coronary sulcus which returns deoxygenated blood from the heart muscle to the right atrium.
*small cardiac veins drain directly into the Atrium
Valves
Atrioventricular Valves (AV): located between the right Atrium and the Right Ventricle, as well as between the left Atrium and the left Ventricle

• the valve between the right Atrium and Ventricle is called the Tricuspid valve
• the valve between the left Atrium and Ventricle is called the Bicuspid valve
  • these valves allow blood flow from the atria into the ventricles, but they prevent the blood from flowing back.
• When the ventricles relax, the higher pressure in the Atria forces the AV valves to open up and blood flows from the Atria to the ventricles

Aortic and Pulmonary Semilunar Valves:

• Consist of three pocketlike halfmoon-shaped cups
• When the ventricles contract the increasing pressure forces these valves to open
• When the ventricles relax the pressure in the aorta is higher than the pressure in the ventricles and Pulmonary Trunk
  • The pattern of blood flows back from the Aorta through the ventricles`

This is a picture showing the small cardiac veins and the coronarty arteries